Application of hybrid macro/mesoscopic method to non-equilibrium flow past a square cylinder

Abstract A hybrid macroscopic and mesoscopic approach is proposed in the simulation of the non-aquarium rarefied gas past a square cylinder. Both the classical discrete velocity method and the moment method are directly given in the present study. The computation accuracy of the hybrid scheme has been compared with results obtained from the classical paper in the continuum regime. Both the full discrete velocity method and the hybrid scheme are used in simulating rarefied gas flow past a square cylinder in the early transition regime. The simulation results indicate that the computational memory usage is reduced from about 171.52GB to 1.84GB. The computational time cost is reduced from 1355min to 323min. The drag coefficient and the vortice size calculated from the hybrid scheme and the DVM are almost identical.